The present invention relates to digital image processing.
A thumbnail is a digital image that is usually but need not be static. Thumbnails are usually displayed at a small size so that more than one can fit in a display area of a display device. A size of a displayed thumbnail is the spatial extent of the display area consumed by the thumbnail. Display size is typically measured in units of squared pixels. For thumbnails that are rectangular in shape, the size of the displayed thumbnail is calculated by taking the product of its height and width, both usually measured in units of pixels.
A rectangular thumbnail has an inherent aspect ratio, which is the ratio of the width and the height of the thumbnail. The inherent aspect ratio of a thumbnail is generally determined by the application and/or device that generated the thumbnail. A rectangular thumbnail can be displayed at an aspect ratio that is different than its inherent aspect ratio by, for example, cropping or uneven scaling of its height and width.
Aspect ratio is generally described as either width to height or, alternatively, width:height. A thumbnail having, for example, a displayed height and width of 400 pixels by 300 pixels, respectively, has a display aspect ratio of 4 to 3 or simply 4:3.
An application that displays thumbnails usually provides an image scaling tool that can be used to change the display size of the thumbnails. The scaling tool typically includes multiple positions. The selection of a position scales the thumbnails to a target display height and a target display width that are associated with the position.